udldrmfb: udl_get_edid: usb_control_msg buffer must not be on the stack

The buffer passed to usb_control_msg may end up in scatter-gather list, and
may thus not be on the stack. Having it on the stack usually works on x86, but
not on other archs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>